package com.situ.day250109;

import org.junit.Test;

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello World");
        //soutm
        System.out.println("HelloWorld.main");
    }

    //变量 variable
    int age1 = 12;
    int age2 = 13;
    //常量 值不能改
    final int age3 = 20;

    @Test
    public void test1() {
        char ch = 'a';
        System.out.println(ch);
        System.out.println(ch + 1);
        System.out.println((char) (ch + 1));

        double d = 3.14;
        int num = (int) d;
        System.out.println(num);
    }
}
